From: Zdenek Kabelac <zkabelac@redhat.com>

Add missing del_gendisk() to error path when creation of workqueue fails.
Otherwice there is a resource leak and following warning is shown:

WARNING: at fs/sysfs/dir.c:487 sysfs_add_one+0xc5/0x160()
sysfs: cannot create duplicate filename '/devices/virtual/block/dm-0'

Cc: stable@kernel.org
Signed-off-by: Zdenek Kabelac <zkabelac@redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

---
 drivers/md/dm.c |    1 +
 1 file changed, 1 insertion(+)

Index: linux-2.6.31/drivers/md/dm.c
===================================================================
--- linux-2.6.31.orig/drivers/md/dm.c
+++ linux-2.6.31/drivers/md/dm.c
@@ -1822,6 +1822,7 @@ static struct mapped_device *alloc_dev(i
 bad_bdev:
 	destroy_workqueue(md->wq);
 bad_thread:
+	del_gendisk(md->disk);
 	put_disk(md->disk);
 bad_disk:
 	blk_cleanup_queue(md->queue);